Category bias in facial memory

Existing knowledge has been shown to interact with episodic information in a variety of memory tasks. The present study examined a known bias due to existing knowledge in the context of memory for facial features. Specifically, we examined if the category bias, a systematic error in remembering a target toward the prototypical location of its region, increased as a function of distance away from its prototypical location and if time and degree of distortion moderated the bias. We manipulated eye width along a horizontal axis to create a set of face stimuli. In Experiment 1, participants saw one face at a time, and after a short delay, they were asked to reproduce the location of one of the eyes and complete a recognition task. In Experiment 2, we increased the delay from 2000ms to 5000ms. We hypothesized and found that bias towards the prototype increased for the moderately distorted face conditions; however, the decrease in bias in the highly distorted conditions was not statistically significant. Additionally, bias did not increase over time. We discuss our results in the context of Huttenlocher et al.'s (1991) category adjustment model, as well as the practical implications of our study in the field of eyewitness memory.